JP5075733B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor used for applications such as a refrigerant compressor and an air compressor for refrigeration and air conditioning, and more particularly to a scroll compressor using a self-starting synchronous motor.

  A conventional scroll compressor using a self-starting synchronous motor is disclosed in Patent Document 1.

JP 2007-330060 A

  The scroll compressor described in Patent Document 1 drives a compression mechanism unit with a two-pole self-starting synchronous motor. The motor is composed of a squirrel-cage induction machine and a permanent magnet, and an inverter. It has the feature that a synchronous motor can be started by a commercial power supply without going through. In such a self-starting synchronous motor, the starting torque of the squirrel-cage induction machine needs to be larger than the sum of the repulsion torque by the permanent magnet and the gas compression torque. For this reason, it is necessary to increase the size of the squirrel-cage induction machine part as compared with the one using the induction motor composed only of the squirrel-cage induction machine. In addition, depending on the rotor position immediately before the start of the electric motor, a large starting torque is generated by superimposing the starting torque of the squirrel-cage induction motor and the torque of the permanent magnet, the compressor swings greatly, and the base that supports the compressor and A large stress was generated in the piping system around the compressor, which could cause a decrease in reliability such as cracks and breakage.

  In addition, since a large torque is required at the time of starting relative to the torque at the rated rotation at the time of starting, it is necessary to equip a motor with a large physique against the motor physique to output the necessary torque at the rated rotation. there were.

  An object of the present invention is to obtain a highly reliable compressor capable of reducing the size of a self-starting synchronous motor in a scroll compressor using the self-starting synchronous motor.

  Another object of the present invention is a bypass passage that is provided in a fixed scroll and returns gas in a compression chamber formed by the two scrolls in the compression mechanism section to the suction side, and a slide-type valve mechanism that opens and closes the bypass passage. In order to obtain a highly reliable compressor that can stably open and close the bypass passage without causing a twist, the sliding valve mechanism can be stably slid. It is in.

  In order to achieve the above object, the present invention provides a compression mechanism unit configured by combining a scroll of a fixed scroll and an orbiting scroll formed by standing a spiral wrap on a disc-shaped end plate, and a rotation for driving the orbiting scroll. In a scroll compressor comprising a shaft, a bearing that rotatably supports the rotating shaft, and a self-starting synchronous motor that drives the rotating shaft, the both scrolls provided in the fixed scroll and in the compression mechanism section A bypass passage for returning the gas in the compression chamber to the suction side, a slide-type valve mechanism provided so that the bypass passage can be opened and closed, and the slide-type valve mechanism to urge the compression chamber side toward the compression chamber A driving spring provided in the fixed scroll, and the sliding valve mechanism includes a pressure in a discharge space formed on a back side of the fixed scroll, and a front Differential pressure between the pressure in the compression chamber, and is configured to be actuated by a spring force of the drive spring, the drive spring, characterized in that it protrudes into the discharge space than the fixed scroll back.

  Another feature of the present invention is that a compression mechanism unit configured by combining both scrolls of a fixed scroll and a orbiting scroll formed by standing a spiral wrap on a disc-shaped end plate, a rotating shaft for driving the orbiting scroll, In a scroll compressor including a bearing that rotatably supports the rotating shaft and an electric motor that drives the rotating shaft, the scroll compressor is provided in the fixed scroll and is formed in the compression chamber formed by the two scrolls in the compression mechanism section. A bypass passage for returning the gas to the suction side, a slide-type valve mechanism provided so as to be able to open and close the bypass passage, and the fixed scroll provided to urge the slide-type valve mechanism toward the compression chamber side. The sliding valve mechanism includes a differential pressure between the pressure in the discharge space formed on the back side of the fixed scroll and the pressure in the compression chamber, and Is configured to be actuated by a spring force of the drive spring, the drive spring is to provided to protrude into the discharge space than the fixed scroll back.

  Here, the drive spring that biases the sliding valve mechanism moves in a direction in which the spring extends when the valve mechanism moves in a direction to close the bypass passage, and in a direction in which the bypass passage opens. When doing, it is good to be comprised so that it may become a direction which a spring contracts.

  The bypass passage is preferably provided at a position advanced about 360 degrees (2π) from the suction position in the spiral wrap of the fixed scroll, that is, a position approximately rotated once.

  Furthermore, a seal member for sealing the compressor discharge space and the compression chamber in the lap is provided in the circumferential direction in the slide type valve mechanism, and this seal member may be an annular packing having a V-shaped cross section. .

The present invention provides a bypass passage provided in a fixed scroll for returning the gas in the compression chamber to the suction side, a slide type valve mechanism provided so as to be able to open and close the bypass passage, and the slide type valve mechanism on the compression chamber side. Since the drive spring provided in the fixed scroll is provided so as to be biased, and this drive spring is provided so as to protrude into the discharge space from the back surface of the fixed scroll, the following effects are obtained.
(1) In a scroll compressor using a self-starting synchronous motor, the compression torque can be reduced by opening the bypass passage and returning the gas in the compression chamber to the suction side at the time of starting. Can be downsized. In addition, since the starting torque can be reduced, it is possible to prevent a large amount of stress from occurring in the base that supports the compressor and the piping system around the compressor due to a large swing of the compressor during starting, and reliability that prevents cracks and breakage. A high scroll compressor can be obtained.
(2) In a scroll compressor that is provided on the fixed scroll and includes a slide valve mechanism that opens and closes a bypass passage that returns the gas in the compression chamber to the suction side, a drive spring that biases the slide valve mechanism toward the compression chamber Is provided so as to protrude from the back of the fixed scroll into the discharge space, so that the sliding length of the sliding valve mechanism can be increased. A highly reliable compressor capable of opening and closing a stable bypass passage can be obtained.

  In a scroll compressor that uses a self-starting synchronous motor, the starting torque of the squirrel-cage induction machine needs to be larger than the sum of the repulsion torque by the permanent magnet and the gas compression torque, and immediately before starting the motor. Depending on the rotor position, a large starting torque is generated by superimposing the starting torque of the squirrel-cage induction motor and the torque generated by the permanent magnet, and the compressor swings greatly to generate a large stress in the piping system around the compressor. There's a problem. In addition, since a large torque is required at the time of starting relative to the torque at the rated rotation at the time of starting, it is necessary to equip a motor with a large physique against the motor physique to output the necessary torque at the rated rotation. is there.

  In order to solve this problem, as a structure capable of reducing the starting torque of the squirrel-cage induction machine, a configuration is provided in which a bypass passage for returning the gas in the compression chamber to the suction side is provided in the fixed scroll, and a valve mechanism for opening and closing the bypass passage is provided. investigated.

  As what provided the bypass scroll and the slide-type valve mechanism in the fixed scroll of a scroll compressor, there exist some which are described in patent 2471709, for example. However, when this slide type valve mechanism is adopted, the spring for energizing the valve is installed inside the slide part, so the slide part length of the valve is reduced, which makes it easy to cause valve twisting and reliability. May decrease.

  Therefore, in the present invention, the drive spring for urging the valve mechanism is installed on the upper part of the slide portion of the valve mechanism, so that a sufficient slide length can be secured. According to the present invention, when a large bypass flow rate is to be ensured with a large-capacity compressor or the like, even if the slide length is increased, the valve is not twisted and a highly reliable compressor is obtained.

  In addition, since the slide type valve mechanism is provided on the suction side of the compressor, the valve mechanism is opened by the force of the spring before and after the start of the compressor, and the gas in the compression chamber is bypassed to the suction side. Therefore, the compressor discharge amount is reduced, and the gas compression torque can be reduced. When the pressure in the compressor discharge space rises after starting, the differential pressure between the discharge pressure and the compression chamber in the scroll wrap gradually increases.If this differential pressure exceeds the spring force, the valve mechanism closes, so the compressor The engine is operated with a normal discharge amount.

  According to the present invention, since the gas compression torque at the time of starting can be reduced, a design in which the starting torque of the squirrel-cage induction machine part of the self-starting synchronous motor can be suppressed to be small, and the self-starting synchronous motor can be reduced in size. In addition, the scroll compressor provided with the self-starting synchronous motor that is inexpensive and highly reliable can be obtained.

  Furthermore, by providing a seal member that seals the compressor discharge space and the compression chamber in the wrap in the circumferential direction in the sliding valve mechanism, and making this seal member an annular packing having a V-shaped cross section, The sealing performance of the sealing member is automatically adjusted by the differential pressure between the discharge space and the compression chamber. For this reason, when the differential pressure where sliding characteristics are prioritized over the sealing performance during valve mechanism operation is small, sliding resistance can be kept small, and there is a large differential pressure where sealing performance after valve closing is prioritized. In some cases, a large sealing performance can be exhibited, the seal member is not seized, and a more reliable compressor can be obtained.

  Specific embodiments of the present invention will be described below with reference to FIGS. In each figure, the parts denoted by the same reference numerals indicate the same or corresponding parts.

  1 is a longitudinal sectional view of a scroll compressor showing Embodiment 1 of the present invention, FIG. 2 is a longitudinal sectional view of a sliding valve mechanism shown in FIG. 1, and FIGS. 3 and 4 are when the sliding valve mechanism is opened. It is a figure which shows the time of closing.

  The scroll compressor 1 is configured by storing the compression mechanism unit 2, the drive unit 3, the rotating shaft 300, and the like in a sealed container 700. Inside the sealed container is a vertical scroll compressor arranged in the order of the compression mechanism part 2, the drive part 3 and the oil sump 730 from above, and the compression mechanism part 2 and the drive part 3 are connected via a rotating shaft 300. Has been.

  The compression mechanism unit 2 includes a fixed scroll 100, a turning scroll 200, and a frame 400 as basic elements. The frame 400 is fixed to the hermetic container 700 and constitutes a member for disposing the rolling bearing 401. The fixed scroll 100 includes a base plate 101, a scroll spiral body 102, a suction port 103, and a discharge port 104 as basic components, and is fixed to the frame 400 with bolts 405. A scroll spiral body (spiral wrap) 102 is erected vertically on one side of a base plate (end plate) 101. The orbiting scroll 200 includes a base plate (end plate) 201, a scroll spiral body (spiral wrap) 202, an orbiting scroll bearing portion 203, a slide bearing 210 disposed on the orbiting scroll bearing portion 203, and a back provided on the base plate. A pressure hole (not shown) is configured as a basic component. The scroll spiral body 202 is erected vertically on one side of the base plate 201. The orbiting scroll bearing 203 is formed so as to protrude perpendicularly to the other side (anti-spiral body side) of the base plate 201. The orbiting scroll 200 is formed by processing each component from a casting made of cast iron or aluminum.

  The compression chamber 130 configured by meshing the fixed scroll 100 and the orbiting scroll 200 is subjected to a compression operation in which the volume thereof decreases as the orbiting scroll 200 orbits. In this compression operation, the working fluid is sucked into the compression chamber 130 through the suction pipe 711 and the suction port 103 in accordance with the turning motion of the turning scroll 200, and the sucked working fluid passes through the compression stroke and is fixed to the fixed scroll 100. The liquid is discharged from the discharge port 104 into the sealed container 700 and further discharged from the sealed container 700 via the discharge pipe 701. Thereby, the space in the sealed container 700 is kept at the discharge pressure. A high-pressure refrigerant such as R410A that is friendly to the global environment is used as the working fluid that is compressed by the compression mechanism.

  The sealed container 700 has an upper cap 710 and a lower cap 720. The upper cap 710 and the lower cap 720 are fitted so as to cover the center tube portion of the sealed container, and the fitting end portions are heated and welded obliquely from below and obliquely upward by a welding torch. A leg portion 721 is attached to the bottom surface of the sealed container 700. A magnet 722 is attached to the inside of the lower cap 720 and plays a role of collecting dust in the compressor.

  A hermetic terminal 702 and a terminal cover 703 are provided on the side surface of the hermetic container 700 so that electric power can be supplied to the electric motor 600. The hermetic terminal 702 is provided through the hermetic container 700 and is positioned between the end coil of the stator 601 and the frame 400. On the side surface of the sealed container 700 opposite to the hermetic terminal 702, a discharge pipe 701 is provided to penetrate the sealed container 700 and is provided above the balance weight 407.

  The drive unit 3 that orbits the orbiting scroll 200 includes an electric motor 600 including a stator 601 and a rotor 602, a rotating shaft 300, an oil supply pump 900, an Oldham joint 500 and a frame 400 that are main components of the rotation prevention mechanism of the orbiting scroll 200, and rolling. The bearings 401, 803, the orbiting scroll bearing portion 203, and the plain bearing 210 disposed in the orbiting scroll bearing portion 203 are configured as basic elements.

  The rotor 602 includes a number of squirrel-cage windings 605 for starting and a permanent magnet 607 mainly composed of a rare earth embedded in a magnet insertion hole 606 inside a rotor core 604 provided on the rotating shaft 300. The arrangement is made so that the number of poles is two. A space between the magnetic poles of the permanent magnet 607 is constituted by holes and a magnetic body, and the circumferential pitch angle θ of the magnetic body is configured to be larger than the sum of the bridge angles included in one pole of the permanent magnet 607. Has been. The magnetic body portion may be configured by punching out a silicon steel plate to form holes and then inserting iron or the like newly, or may be configured without punching out the silicon steel plate. The rotor core 604 may be a powder compact such as a dust core. Furthermore, the rotor core 604 and the permanent magnet 607 may be formed by integral molding.

  The rotating shaft 300 integrally includes a main shaft portion 302, a crankpin 301, and a sub bearing support portion 303. The main shaft portion 302 and the auxiliary bearing support portion 303 are formed on the same shaft center, and constitute a main shaft portion. Further, an oil supply pump 900 is press-fitted into the lower end portion of the rotary shaft 300. The rolling bearings 401 and 803 constitute a rotating shaft support portion that rotatably engages the main shaft portion 302 and the sub bearing support portion 303 of the rotating shaft 300. The orbiting scroll bearing portion 203 is provided in the orbiting scroll 200 so that the sliding bearing 210 is press-fitted into the inner diameter of the orbiting scroll bearing portion 203 so that the crank pin 301 of the rotating shaft 300 can be moved and rotated in the thrust direction that is the rotating shaft direction. It has been.

  The rolling bearing 401 is arranged on the upper side of the electric motor 600, and the rolling bearing (sub bearing) 803 constituting the main part of the auxiliary bearing portion 800 is arranged on the lower side of the electric motor 600. Rolling bearings 401 and 803 constitute main shaft bearings that support main shaft portions on both sides of electric motor 600. In this embodiment, since the main shaft portions are supported by the rolling bearings 401 and 803 on both sides of the electric motor 600, the main shaft portion of the rotating shaft can be prevented from being tilted while suppressing power loss of the main shaft bearing. .

  The rolling bearing 803 constitutes a main part of the auxiliary bearing unit 800. A housing 802 is fixed to the lower frame 801 fixed to the hermetic container 700 via bolts 805. A rolling bearing 803 is inserted into the housing 802 from above, and a housing cover 804 is further attached from above.

  The oil supply pump 900 is a centrifugal pump attached to the lower end of the rotary shaft 300, and the lubricating oil stored in the oil sump 730 is forcibly passed through the oil supply hole 901, the auxiliary bearing 803, the orbiting scroll bearing portion 203, and Is provided to supply and lubricate the rolling bearing 401. The oil supplied to the oil supply hole 901 is also supplied to the sliding portion between the orbiting scroll 200 and the fixed scroll 100. The oil supply hole 901 is provided so as to vertically penetrate the rotary shaft 300, and has a lower oil supply hole concentric with the axis of the rotary shaft 300 and an upper oil supply hole eccentric with respect to the axis of the rotary shaft 300. doing. A lateral oil supply hole communicating with the lower oil supply hole is provided to supply oil to the auxiliary bearing 803.

  The Oldham joint 500 is disposed on the back surface of the base plate 201 of the orbiting scroll 200. One set of two orthogonal key portions formed on the Oldham joint 500 slides on a key groove which is a receiving portion of the Oldham joint 500 formed on the frame 400, and the other set is configured on the back side of the scroll spiral body 202. Slide the keyway. As a result, the orbiting scroll 200 orbits within the plane perpendicular to the axial direction, which is the direction in which the scroll spiral body 202 is erected, without rotating with respect to the fixed scroll 100.

  When the crankpin 301 rotates eccentrically due to the rotation of the rotary shaft 300 connected to the electric motor 600, the compression mechanism unit 2 performs a turning motion without rotating with respect to the fixed scroll 100 by the rotation preventing mechanism of the Oldham joint 500. Thereby, the gas is sucked into the compression chamber 130 formed by the scroll spiral body 102 and the scroll spiral body 202 via the suction pipe 711 and the suction port 103. Due to the orbiting motion of the orbiting scroll 200, the compression chamber 130 decreases in volume while moving to the central portion, compresses the gas, and discharges the compressed gas from the discharge port 104 to the discharge chamber. The gas discharged into the discharge chamber circulates around the compression mechanism unit 3 and the electric motor 600 and is then discharged from the discharge pipe 701 to the outside of the compressor.

  The base plate 201 of the orbiting scroll 200 is provided with a back pressure hole (not shown) that allows the compression chamber 130 and the back pressure chamber 411 on the orbiting back surface to communicate with each other. The pressure is maintained at an intermediate discharge pressure (intermediate pressure). The back pressure chamber 411 configured on the back side of the orbiting scroll 200 is a space formed by being surrounded by the orbiting scroll 200, the frame 400, and the fixed scroll 100. Therefore, the frame 400 also serves as a member that forms the back pressure chamber 411. A seal ring 410 provided in the groove of the frame 400 prevents discharge gas from flowing into the back pressure chamber 411.

  The inner diameter of the seal ring 410 is smaller than the outer diameter of the rolling bearing 401. In order to be able to adopt such a configuration, the rolling bearing 401 is inserted into the frame 400 from the rotation driving means side of the frame 400, and the inserted rolling bearing 401 is fixed by the frame cover 403. A thrust bearing 402 is provided on the frame cover 403. The frame cover 403 is formed separately from the frame 400. The frame cover 403 is fixed to the frame 400 with bolts 406. By fixing the bolts in this manner, the gap between the frame cover 403 and the frame 400 can be accurately sealed, so that oil leakage from the oil supply path can be suppressed. The frame cover 403 includes a portion that is inserted inside the frame 400 and presses the rolling bearing 401, and a portion that contacts and is fixed to the end surface of the frame 400 on the side of the rotation driving means.

  The balance weight 407 is provided on the rotating shaft 300 so as to be positioned on the electric motor side (counter crank pin side) with respect to the rolling bearing 401 that is a main shaft bearing. In this embodiment, the balance weight 407 is formed separately from the rotary shaft 300 and is press-fitted and fixed to the rotary shaft 300. However, the balance weight 407 is provided integrally with the rotary shaft 300. May be. The maximum outer diameter portion 407a of the balance weight 407 is provided so as to protrude from the end face side of the coil end of the stator 601, and has a larger diameter than the inner diameter of the coil end.

  Next, the oil supply path will be described. When the rotating shaft 300 is rotated, the oil in the oil reservoir 730 is boosted and supplied to the oil passage 311 in the rotating shaft by the oil supply pump 900. Part of the oil sent to the oil passage 311 flows through the lateral hole 312 to the auxiliary bearing 803 that is a rolling bearing, and then returns to the oil reservoir 730. The oil that reaches the upper part of the crankpin 301 through the oil passage 311 passes through the slide bearing 210 and further flows into the rolling bearing 401. Most of the oil that has lubricated the rolling bearing 401 passes through the oil drain pipe 408 and returns to the oil sump 730.

  An oil supply pocket 205 is provided on an end surface of the orbiting scroll bearing portion 203 of the orbiting scroll 200, and the oil supply pocket 205 reciprocates between the outer side and the inner side of the seal ring 410 as the orbiting scroll 200 reciprocates. And part of the oil between the rolling bearings 401 is conveyed to the back pressure chamber 411. The conveyed oil is supplied to the Oldham coupling 500 and then supplied to the end face 105 of the fixed scroll and the sliding face of the base plate 201 of the orbiting scroll 200.

  The oil conveyed to the back pressure chamber 411 flows into the compression chamber 130 through the back pressure hole or through a minute gap on the sliding surface of the end plate. The oil flowing into the compression chamber 130 is discharged from the discharge port 104 together with the compressed refrigerant gas, separated from the refrigerant gas in the sealed container 700, and returned to the oil sump 730.

  Next, the flow of oil and refrigerant gas discharged from the discharge port 104 of the fixed scroll 100 will be described. The oil and the refrigerant gas discharged from the discharge port 104 pass through a passage 421 provided on the outer periphery of the fixed scroll 100 and the frame 400 and flow into a D hole 423 provided below the leg portion 422 of the frame 400. The D-shear 423 has two flow paths, a minute gap 424 provided at the lower end and a window 425 provided in the inner peripheral direction of the sealed container 700, and the oil and refrigerant gas flowing into the D-shear 423 Most of the air flows along the inner periphery of the hermetic container 700 through the window 425 provided in the inner peripheral direction of the hermetic container 700 and through the space between the frame 400 and the stator 601. Part of the oil and refrigerant gas that has passed through the minute gap 424 provided at the lower end of the D clearance 423 is used for cooling the lower portion of the stator 601 through the stator outer peripheral passage 603 provided in the outer periphery of the stator 601.

  The oil and refrigerant gas flowing along the inner periphery of the sealed container 700 are separated from the refrigerant gas by the action of centrifugal force so that the oil having a high specific gravity adheres to the inner periphery of the sealed container 700. The separated oil returns to the oil sump 730 through the stator outer peripheral passage 603. The refrigerant gas is discharged to the outside of the sealed container 700 through the discharge pipe 701.

  As shown in FIG. 2, the bypass valve (valve mechanism) 106 installed on the fixed scroll 100 includes a valve 107, a packing 108, a spring (drive spring) 109, and spring retainers 112 and 113. When stopped, the bypass valve 106 is pushed upward by the spring force of the spring 109 as shown in FIG. In the cylinder 110 in which the valve 107 is inserted and installed, a lateral hole 111 communicated to the suction side of the compression chamber 130 is arranged. As shown in FIG. 3, when the valve 107 is pushed upward, it communicates. However, as shown in FIG. 4, when the valve 107 is pushed downward, the structure is closed. The horizontal hole 111 and the cylinder 110 form a bypass passage that communicates the compression chamber and the suction side.

  After the compressor is started, the horizontal hole 111 is in communication until the differential pressure between the discharge space above the compression chamber 130 and the fixed scroll 100 exceeds the spring force of the spring 109. Therefore, the compression start position of the compression chamber 130 is bypassed. From the valve installation position, the apparent discharge amount becomes smaller. Since the apparent discharge amount becomes small, the compression torque of the refrigerant gas becomes small, so that the load on the electric motor can be reduced.

  If the pressure difference between the discharge space above the compression chamber 130 and the fixed scroll 100 exceeds the spring force of the spring 109, the valve 107 is closed as shown in FIG. It is possible to perform gas compression and discharge the necessary compressed gas. The packing 108 attached to the valve 107 is a member for sealing the discharge pressure space above the fixed scroll 100 and the pressure in the compression chamber 130, and it is desirable to use a member with high sealing properties such as an O-ring. In this embodiment, a resin annular ring having a V-shaped cross section is used. However, in the case of a V-shaped annular rig, the pressing force to the cylinder 110 and the valve 107 changes due to the differential pressure. For this reason, when the packing 108 slides during valve operation or the like, since the differential pressure between the discharge space above the compression chamber 130 and the fixed scroll 100 is small, the pressing force of the packing 108 is small and the sliding resistance is small. , Wear and galling are less likely to occur. On the other hand, when the valve 107 is pushed down and is operating normally, the pressure difference between the discharge space above the compression chamber 130 and the fixed scroll 100 is large, so the pressing force of the packing 108 is also large and the sealing performance. Can be fully demonstrated.

  A spring 109 is disposed on top of the valve 107. That is, the spring 109 is provided so as to protrude into the discharge space from the back surface of the fixed scroll. Thus, by installing the spring 109 above the valve 107, a sufficient slide length of the valve 107 can be ensured. For this reason, when it is desired to ensure a large bypass flow rate with a large-capacity compressor or the like, even if the slide length is increased, the valve will not be twisted and a highly reliable compressor can be obtained.

  By installing this bypass valve 106, the discharge amount before start and immediately after start is reduced, and the gas compression torque can be reduced. After starting, the discharge pressure and the pressure difference in the scroll wrap can be made. Therefore, if this pressure difference exceeds the spring force, the valve is closed and operation can be performed with a normal discharge amount.

  According to the present embodiment, since the gas compression torque at the time of starting can be reduced as described above, it becomes possible to design a self-starting synchronous motor with a small starting torque, and the squirrel-cage induction machine portion can be reduced in size. At the same time, it is possible to reduce the whirling at the time of starting, and an inexpensive and highly reliable scroll compressor can be obtained.

  In an induction motor composed only of a squirrel-cage induction machine, if the squirrel-cage induction machine part is made smaller, the rated efficiency and the overload efficiency are also lowered, so the squirrel-cage induction machine cannot be made smaller. However, in the magnet-embedded synchronous motor as in the present embodiment, that is, the self-starting synchronous motor, the squirrel-cage induction unit does not contribute to the operation efficiency because the synchronous operation is performed by the embedded magnet after startup. Accordingly, it is possible to reduce the size of the squirrel cage induction machine, and it is possible to obtain a scroll compressor using a self-starting synchronous motor that is inexpensive and highly reliable.

  As described above, according to the present embodiment, the self-starting synchronous motor can be reduced in size, and a low-cost and highly reliable scroll compressor in which the slide type valve mechanism stably operates and seals is realized. it can.

  In the above embodiment, the scroll compressor using the self-starting synchronous motor has been described. However, the slide valve mechanism described above is also effective when applied to a scroll compressor using a normal motor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a scroll compressor showing Embodiment 1 of the present invention. The expanded sectional view of the slide type valve mechanism part of FIG. The principal part sectional drawing which shows the scroll compressor at the time of opening of a slide type valve mechanism part. The principal part sectional drawing which shows the scroll compressor at the time of closing of a slide type valve mechanism part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Compression mechanism part 3 Drive part 100 Fixed scroll 101,201 Base plate (end plate)
102 scroll scroll (spiral wrap)
103 Inlet port 104 Outlet port 105 End face 106 Bypass valve (valve mechanism)
107 Valve 108 Packing 109 Spring (drive spring)
110 Cylinders 111, 312 Horizontal holes 112, 113 Spring retainer 130 Compression chamber 200 Orbiting scroll 202 Scroll spiral body 203 Orbiting scroll bearing portion 205 Oil supply pocket 210 Sliding bearing 300 Rotating shaft 301 Crank pin 302 Main shaft portion 303 Sub bearing support portion 311 Oil passage 400 Frame 401 Rolling bearing 403 Frame cover 405, 406, 805 Bolt 407 Balance weight 408 Oil drain pipe 410 Seal ring 411 Back pressure chamber 412 Inner back pressure chamber 413 Outer back pressure chamber 422 Frame leg portion 423 D slot 424 Gap portion 425 Window portion 500 Oldham coupling 600 Electric motor 601 Stator 602 Rotor 603 Stator outer peripheral passage 604 Rotor core 605 Start-up cage winding 606 Magnet insertion hole 607 Permanent magnet 700 Sealed container 701 Discharge Tube 702 Hermetic terminal 703 Terminal cover 704 Temperature detection member 705 Temperature detection member fixing member 706 Thermal insulation member 707 Thermal insulation member fixation member 710 Upper cap 711 Suction pipe 720 Lower cap 721 Leg portion 722 Magnet 730 Oil reservoir 800 Sub bearing portion 801 Lower frame 802 Housing 803 Rolling bearing (sub bearing)
804 Housing cover 900 Oil supply pump

Claims (5)

A compression mechanism composed of a fixed scroll and an orbiting scroll that are formed with a spiral wrap upright on a disc-shaped end plate, a rotating shaft that drives the orbiting scroll, and a rotating shaft that rotatably supports the rotating shaft In a scroll compressor comprising a bearing that performs a self-starting synchronous motor that drives the rotating shaft,
A bypass passage provided in the fixed scroll and returning a gas in a compression chamber formed by the two scrolls in the compression mechanism section to the suction side;
A slide-type valve mechanism provided so that the bypass passage can be opened and closed;
And a drive spring provided in the fixed scroll so as to bias the sliding valve mechanism on the opposite side of the compression chamber,
The sliding valve mechanism is configured to operate by a differential pressure between the pressure of the discharge space formed on the back side of the fixed scroll and the pressure in the compression chamber, and the spring force of the drive spring,
The scroll compressor, wherein the drive spring is provided so as to protrude from the back surface of the fixed scroll into the discharge space. According to claim 1, wherein the drive spring that urges the sliding valve mechanism, in the direction in which the spring extends in when the valve mechanism is moved in a direction to open the bypass passage, the direction in which the bypass passage is closed A scroll compressor characterized in that the spring is in a contracting direction when moving to.   3. The scroll compressor according to claim 1, wherein the bypass passage is provided at a position advanced about 360 degrees from a suction position in the spiral wrap of the fixed scroll. A compression mechanism composed of a fixed scroll and an orbiting scroll that are formed with a spiral wrap upright on a disc-shaped end plate, a rotating shaft that drives the orbiting scroll, and a rotating shaft that rotatably supports the rotating shaft In a scroll compressor comprising a bearing that performs the operation and an electric motor that drives the rotating shaft,
A bypass passage provided in the fixed scroll and returning a gas in a compression chamber formed by the two scrolls in the compression mechanism section to the suction side;
A slide-type valve mechanism provided so that the bypass passage can be opened and closed;
And a drive spring provided in the fixed scroll so as to bias the sliding valve mechanism on the opposite side of the compression chamber,
The sliding valve mechanism is configured to operate by a differential pressure between the pressure of the discharge space formed on the back side of the fixed scroll and the pressure in the compression chamber, and the spring force of the drive spring,
The scroll compressor, wherein the drive spring is provided so as to protrude from the back surface of the fixed scroll into the discharge space. In any one of claims 1 to 4, in the circumferential direction of the valve mechanism of the sliding, the seal member for sealing the said compression chamber and the discharge space is provided, the sealing member, the cross section is V-shaped A scroll compressor characterized by an annular packing.

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